This summer Ernie Scott and his wife, Jan, will get in their customized ‘65 Plymouth ‘Cuda, lovingly painted with a Key West sunset, a Margarita glass on each door, and the words ”Unleaded Tequila Only” circling the gas cap and head for…Margaritaville. And that destination is no less real for being only a state of mind shared by Ernie, a 43-year-old Atlanta bookkeeper, his wife, and tens of thousands of other hardcore fans of singer Jimmy Buffett, the beyond-mellow balladeer whose music evokes a bittersweet tropical paradise. Ernie admits to having seen Buffett perform ”40 or 50” times, and when he cranks up the ‘Cuda to follow this summer’s tour, he and Jan won’t be alone. Paul Harnice, a 25-year-old Frankfort, Ky. law clerk, has seen Buffett in concert 17 times in nine years. Pat Dorwin, a 51-year-old Indianapolis grandmother, has attended ”10 or 15” of his concerts since 1980 and promises to be one of the first in line when Buffett plays her hometown Aug. 11. They are all Parrot Heads, Buffett fans whose dedication to the singer has created one of the happiest and most unusual pop cultural ”cults” on the globe. Parrot Heads dream of what Buffett’s music represents — escape from the humdrum world to a land of balmy breezes where frozen concoctions buzz in the blender, the beach is never crowded, and life is a perpetual party. ”Through Jimmy, they can feel as if that’s the way they’d be living if they didn’t have the four kids and the job at the factory,” says Carol Shaughnessy, a former Buffett associate who answered the singer’s fan mail for two-and-a-half years.

Buffett, 43, who crafts a sunny variant of calypso, salsa, country, and Memphis soul described as ”yacht rock” or ”gulf and western,” has earned two platinum and three gold records since his recording debut in 1970. But his most remarkable achievement has been the marketing of the Margaritaville mystique.

Through souvenirs, a best-selling book, and the party ambience encouraged at his concerts, he has created a profitable fantasyland in which his followers feel both safe and adventurous. Buffett himself is another matter. Press shy and frequently dismissive of his public, he is as elusive, and some say as cynical, as his fans are avid and sincere. Parrot Head Pat Dorwin says she’s heard all that, but cheerily reports that ”whenever I’ve been around him he’s always been the same way. He’s always been on stage.”

Parrot Heads can be almost any age: baby boomers in their late 30s and early 40s who hopped the first wave of Buffettmania when the record ”Margaritaville” hit the charts in 1977; the current college crowd, for whom Buffett is as much a part of fraternity life as food fights and keg parties; people pushing 60 who look forward to retirement in a sunny Margaritaville-like locale. The obsession, which tends to afflict males more than females, cuts across social classes and includes everyone from yuppies to good old boys.

Whether Buffett is singing about lost days and longing (”Come Monday”), low humor (”My Head Hurts, My Feet Stink and I Don’t Love Jesus”), or rampant hedonism (”Why Don’t We Get Drunk (and Screw)”), he strikes a chord among millions who enjoy his sense of life’s absurdities. ”His general appeal is his attitude,” explains Beverley Kagayama, 35, a Toronto resident. ”If I go home from a nasty day and I’m feeling particularly miserable, almost any Jimmy Buffett song will remind me that life is not so bad.” When Kagayama’s mother died last November, she convinced the family to play Buffett’s ”Take Another Road” at the end of the funeral service.

That song, from Buffett’s current album, Off to See the Lizard, is also the title of a story in Buffett’s best-selling book, Tales From Margaritaville, a collection of tales that retool the themes of boyish naughtiness frequently found on his records. His editor, Bonnie Ingber, expected the book to sell a very respectable 100,000 copies. Published last fall, the book is now in its ninth printing, with some 300,000 copies sold.

Although Buffett has always thought of his fans as people ”who read a little bit and think a little more,” no one was more surprised by literary success than the singer himself, especially since, as his friend and occasional cowriter Marshall Chapman points out, ”he never gets in the singles charts anymore.”

But Buffett, it turns out, is a bird from a different nest, a performer who can sell 350,000 albums without airplay and an author who can make the national best-seller lists without going on an author tour to promote his book.

”It’s not that much of a mystery,” says country singer Tom T. Hall, himself the author of several books of fiction. ”I wouldn’t want to come out with a book of short stories called Watermelon Wine (a reference to Hall’s 1973 hit, ”Old Dogs, Children and Watermelon Wine”). But if you’re Jimmy Buffett, and you write a book and title it Tales From Margaritaville, the millions of people who know the record and want more Margaritaville will buy it.”

Indeed, the symbiotic relationship between Buffett’s music, short stories, and status as a cult figure is a profitable one, as his $2 million-a-year souvenir business attests. Margaritaville baseball caps, visors, snack trays, shorts, T-shirts, and mugs are sold out of his Margaritaville Store in Key West and by mail order through his newsletter, The Coconut Telegraph (circulation 20,000). In the words of his congenial mail-order manager, Martin Lehmann, the business ”just keeps growing. I’ve been here since ‘85, and each successive month has been better than the last.”

Buffett, who, despite his laid-back image, often sounds like a modern-day P.T. Barnum, has remarked to journalist Pat Jordan that he started his store because ”I figured if I couldn’t have my music career anymore, I could still capitalize on my audience.” Surely many of his fans seem as interested in his image and his events as in his music. Each summer, Parrot Heads and their children dress in outrageous outfits and perch faux parrots on their shoulders to party at his concerts.

”It’s an amazing thing to witness,” declares Chapman, who opened for Buffett on his 1987 tour. ”You’d drive up to the show, and there’d be a guy who’d filled up the back of his pickup with water, and he’d be floating on a raft, sipping one of those little drinks with an umbrella in it. And the sheer numbers — 23,500 showed up in Chicago. It was Woodstock every night.”

But Buffett’s music has also inspired an altruistic reaction. Last year 33-year-old Scott Nickerson, who works in guest services for a major hotel chain, started the Atlanta Jimmy Buffett Parrot Head Club, which is not so much a traditional fan club as a gathering of Buffett buffs who volunteer for charity and environmental work. Now Anna Ledbetter, 25, has done the same thing in Colorado, in part because she admires Buffett’s stand on ecological issues (such as Save the Manatee) and because she believes the singer, whom ; she has never met, is ”a real down-to-earth, genuine person.”

In truth, however, the majority of Buffett fans — including Ernie Scott, who has bought a $70,000 house in Key West in the hope of working in Buffett’s Margaritaville Cafe — have no idea who he really is, or how much distance lies between the man and his image. Beneath his likable rogue persona, Buffett can display an arrogance that has caused some Key West natives to call him ”Jimmy Stuffit” for his occasional rude treatment of fans.

For concertgoers, though, it hardly matters. With every ticket the fans buy, they get a piece of the lifestyle, a dream that ultimately has little to do with music or souvenirs or even the singer himself. As Buffett has said, ”I put on a good show for my fans. I sell them Jimmy Buffett. I’m one of the few living legends left Even if radio stations won’t play my songs, I can still be happy. I can still say, ‘I tricked them again.”’